//
// Created by Semir on 2020/4/24.
//

#include <iostream>

using namespace std;

const int MAX_N = 205;
const int MAX_K = 7;
int n, k;
int count[MAX_K][MAX_N];

int main() {
    cin >> n >> k;
    for (int i = 0; i <= k; i++) {
        count[i][i] = 1;
    }
    for (int i = 1; i <= n; i++) {
        count[0][i] = 0;
    }
    for (int i = 1; i <= k; i++) {
        for (int j = i; j <= n; j++) {
            count[i][j] = count[i - 1][j - 1] + count[i][j - i];
        }
    }
    cout << count[k][n] << endl;
    return 0;
}